1. Field of the Invention
The invention relates to a pivotable binding system between a sports device and a tread surface for a user's foot.
2. Description of the Prior Art
WO 96/37269 A1 discloses a device for binding a shoe to a sports device. This device comprises a top part frame, which can be connected to a user's shoe, and pivotably connected to a bottom part frame by means of a hinge mechanism comprising a plurality of linking arms and joints designed to be fixed to various sports devices. The linking mechanism connecting the top to the bottom part frame is constructed so that a pivoting movement of the top part frame relative to the bottom part frame simultaneously causes the two part frames to slide relative to one another. Return spring means are additionally provided which elastically push the two part frames against one another into a predefined relative position. The disadvantage of this system is that correct operation can be easily impaired under difficult conditions of use.
WO 87/01296 A1 describes a binding system between a shoe and a sports device, in particular a binding for a touring ski, in which the articulated link to the sports device is disposed in the region assigned to the ball of the foot. As a result, the binding system for the user's shoe can be displaced into an upper, active position, which permits a pivoting action relative to the sports device about the articulated binding, and a lower, locked position in which the binding is prevented from pivoting. The disadvantage of this system is that it is difficult to switch the articulated binding from the active into the locked position and vice versa and the shear forces or twisting forces which occur between the sports device and the user's foot relative to a vertical axis place high demands on the parts used. Furthermore, when the binding system is in the active position, the central region of the sports device underneath the user's -shoe is placed under a high degree of strain due to the fact that the bearing points are small in surface area or linear in shape. Another disadvantage is the fact that the front region of the sports device may rise if the user leans backwards.
FR 2 573 317 A1 discloses a binding system between a shoe and a sports device, which enables both a pivoting movement of the shoe relative to the sports device about a pivot axis running transversely to its longitudinal axis and, simultaneously, a relative displacement of the shoe in the longitudinal direction of the sports device. The disadvantage of this is that the user of this binding system is unable to get a firm hold on the sports device, which reduces performance. Another disadvantage is that the kickoff which can be achieved with this system is difficult to control and a certain amount of instability in the kickoff is unavoidable, particularly if there is a change in ground conditions.